TREC Tairāwhiti recovery update

Issue 33

31 October 2025

Tēnā koe

In this edition, you’ll learn why crews are hand-placing hundreds of rocks to fix a slip on State Highway 35 (SH35) in Tōrere, what’s coming up for managing water in the Mangahauini Gorge,  what's next for the Hikuwai Bridge replacement, along with our other projects on State Highway 2 (SH2).

We also share more on our TREC summer safety sessions, held earlier this month for contractors and staff, reminding us of what matters most – making sure everyone gets home safe.

A good reminder that the people on our worksites are local, they’re your friends and whānau and helping to keep drivers safe.

Kemps Hill Culvert

Crews are on-site this week at SH35 Kemps Hill Culvert to carry out a permanent repair on an underslip.

Temporary works were completed last year to restore the road to 2 lanes and keep traffic moving. This week, a permanent buttress (supporting structure) will be constructed to provide long-term erosion protection, along with road pavement reinstatement.

Traffic lights are in place during daytime hours, and overnight traffic management will switch to a priority give-way.

Work is now underway for a permanent solution at Kemps Hill Culvert.

Completion at Mātāwai Road

Crews have recently completed work at an overslip (above the road) located on SH2 just north of Ormond.

Willow shrubs have been used to stabilise what was a highly erodible slope. Most of these trees were planted from a cherry picker. The remaining were installed using rope access and abseiling down from the top, as the cherry picker couldn’t reach the tip of the slope.

Shrub willow poles were placed in drilled holes, perpendicular to the slope. Being angled straight in ensures their roots can grow into the slope.

Now the team has completed work at Mātāwai Road, there are only 3 remaining active sites on SH2. This includes 2 recovery sites at Otoko Hill (with one soon to be finished) and one of our major projects underway involving flood resilience work at the Hakanui Straight project (Nesbitt’s Dip).

Shrub willow poles being installed at a minimum 10-degree angle to aid stabilisation.

Steady progress at Tōrere

Since starting work on the original 2 slips back in April, the team has had to tackle 2 more emergency slips in the area.

Despite the unexpected extra challenges, they’ve made solid progress at this site.

Remediation work on the most recent slip wrapped up in late October. The crew is now back to reinforcing the MSE wall above the highway.

They’re currently building up the 7th layer, placing specialist ‘terramesh’ and ‘geogrid’ materials to strengthen the slope. Each layer is then carefully handfilled with strategically placed rocks, helping stabilise the hillside and protect the road below.

Why place rocks by hand?

Hand-placing rocks makes sure everything fits just right. It helps lock together the layers and keeps the hillside strong. 

It’s especially important on steep ground like Tōrere, where machine placement could shift the materials or damage other layers.

Crew working on layer 6 of the overslip above the road.

Hakanui Stream takes its new path as flood resilience works progress

The Hakanui Stream is now flowing through a newly shaped channel and a large new culvert (large pipe) near Te Karaka, marking a major milestone in the Hakanui Straight flood resilience project.

The large culvert is 1.8 metres across and designed to carry high volumes of water during flood events. Combined with the new stream channel, it will help reduce flood risk and lower the risk of highway closures in the future.

The Hakanui Stream has been temporarily diverted to allow crews to do the flood resilience works. Before water entered its new path last week, Te Aitanga-a-Māhaki led a karakia (blessing) to honour the mauri of the awa (water) and acknowledge the significance of the shift.

“In te ao Māori, waterways are ancestors, living carriers of whakapapa and life force,” says Morehu Pewhairangi of Te Aitanga-a-Māhaki. “The karakia ensured the transition was made with respect. It reflects the heart of this project: resilience built not just with rock and machinery, but with tikanga, partnership, and deep respect for the land.”

Work on the project is progressing rapidly. The team has been building up the area alongside the road, raising the shoulders and surrounding ground to match the future height of the upgraded highway. This built-up section will eventually become part of the new, higher road.

Traffic changes ahead

In November, traffic will shift onto the newly raised section, so crews can start raising the level along the existing highway alignment.

Two lanes will open temporarily, but it’s not business as usual just yet. Traffic management and a 30km/h speed limit will stay in place, and the road may return to one lane at times as work continues through to mid-2026. Thanks for slowing down and keeping our crew and other drivers safe.

Project website:Hakanui Straight Flood Resilience | NZ Transport Agency Waka Kotahi.

The Hakanui Stream, near Te Karaka, flowing in its new path.

All go in the Mangahauini Gorge

The first 31 hanbars are in place! That’s no small feat, with each weighing between 5 and 10 tonnes. These massive concrete structures will help lock down the riverbed and protect the highway during future storms.

More than 200 of the 1,300 hanbars are now onsite, ready to be placed. Over the coming months, the remainder will arrive, hauled up on large trucks from Hawke’s Bay, where they’re made.

Major earthworks and excavation are well underway, with 29,000 cubic metres of the major slip that originally blocked the highway now cleared.

In November we're going to divert the Mangahauini River back towards its original pre-cyclone path so crews can start repairing the sheet pile wall and adding rip rap (large rocks).

What’s next?

With steep terrain and tricky geology, managing water is key to keeping the gorge stable.

We’re also about to start installing large culverts and bored drains (horizontal drainage systems drilled around 60-metres into the hillside). They let groundwater escape safely, easing pressure on the slopes and help prevent slips. The existing roadside drains will also be upgraded.

More on this, and the upcoming highway upgrade to come.

Project website: SH35 Mangahauini Gorge | NZ Transport Agency Waka Kotahi

Drone shot of hanbars being put in place in the Mangahauini Gorge.

Laying the foundations at Hikuwai

Construction of temporary platforms, crane pads and temporary retaining walls are starting shortly with bridge piling work due to get started in the coming weeks.

Two cranes have now been assembled and will be stationed on either side of the Hikuwai River once the crane pads have been built for them to work from.

Work on the bridge piling will get underway soon with the 16 pile casings, weighing 13,000kg each, being transported to site as they are needed by contractor CLL.

Project website: SH35 Hikuwai Bridge No.1 replacement | NZ Transport Agency Waka Kotahi

Our 280 tonne and 180 tonne cranes assembled and ready for action.

On track at Rototahe

Crews are making progress on our flood resilience site just south of Tolaga Bay at Rototahe.

As well as culvert completion at 2 farm accessways, one on the western and the other on the eastern side (pictured is the western culvert), crews have also almost finished widening the eastern lane.

On completion this 230 metre section of road will be widened by almost 2 metres and lifted by almost one metre to mitigate flooding impacts with major culvert and drainage improvements.

Project website: TREC Rototahe flood resilience | NZ Transport Agency Waka Kotahi

Culvert progress at Rototahe shows one of the 8 new culverts (large pipes) which is 1200mm across in diameter.

Keeping our TREC whānau safe

We’re gearing up for the summer construction season with our wider TREC whānau, from crew members to local subcontractors.

Health and safety sessions are rolling out across the rohe to make sure everyone heads home safe each day.

These hands-on workshops are a chance to connect, reset, and get ready for the busy months ahead.

One of our Gisborne sessions led by the TREC Health & Safety team.

Catch us on the road

Want to kōrero kanohi ki te kanohi (face-to-face)?

TREC joins the Gisborne District Council’s Rural Support Roadshow each month, travelling SH35 to share updates and hear from locals.

Next stops Tuesday November 11: Tokomaru Bay and Te Araroa.

For details, visit The Rural Support Roadshow | Facebook

The Rural Support Roadshows, organised by Gisborne District Council, are a great way to chat to TREC kanohi ki te kanohi (face-to-face).

State highway snapshot

Below is a snapshot of construction works either underway or coming soon. You can also view completed, current and future work sites on our interactive map.

Here are some of the construction terms we use:

• Bund – embankment that creates a barrier
• Buttress – supporting structure
• Counterfort drain – drain that improves slope stability by controlling groundwater
• Gabion wall - baskets filled with rocks
• Hanbar – specially designed interlocking concrete blocks
• MSE (Mechanically Stabilised Earth) – a retaining wall construction technique used to stabilise slopes
• Reno mattress – shallow basket filled with rocks
• Rip rap – large rocks
• Rock revetment – protection
• Scour - erosion
• Shotcrete – sprayed liquid concrete
• Soil anchors/soil nails – a device used to hold, restrain and support structures
• Swale - a shallow, planted channel that slows and filters stormwater
• Willow wall – using willows as ‘living walls’ to stabilise slips

SH2 underway (link to Otoko map and web page)

• Otoko Hill (Site K) - overslip repairs.
• Otoko Hill (Site M) -  underslip repairs.
• Hakanui Straight (formerly called Nesbitt’s Dip) project – flood improvements.

SH2 coming soon

• Faram’s - underslip repairs.

SH35 underway

• Hikuwai Bridge No.1 replacement – enabling (early) works.
• Mangahauini Gabion Wall – Stage 2 – soil nails, buttress and rip rap at the bottom of the existing gabion wall. 
• Mangahauini Gorge – river works, drainage and culvert upgrades, highway repair and rebuild.
• Kopuaroa Slip 1 – reinstate SH35 to 2 lanes by installing a soil anchor and shotcrete wall.
• Tōrere – underslip and overslip repairs.
• Paronga - D9 Gully Site – buttress wall with MSE. Two faults to be repaired to reinstate state highway to 2 lanes.
• Kemps Hill subsidence – buttress repair using a willow wall. Three faults to be repaired to reinstate state highway to 2 lanes.
• Rotokautuku (Waiapu) Bridge repairs – strengthening works.
• Rototahe – flood resilience.

SH35 coming soon

• Rotokautuku (Waiapu) Bridge revetment – scour protection.
• Maraehara – underslip repairs​.
• Uawa River Scour – Two underslips to be repaired to reinstate state highway to 2 lanes.
• Kopuaroa – drainage improvements.
• Paronga (D9) – drainage improvements.

Whakapā mai – Get in touch

• Email us
• Website
• LinkedIn
• Facebook
• Call us: 0800 80 TREC (0800 80 8732)

If you spot an issue at a work site after hours, call 0800 4 HIGHWAYS (0800 444449).

Sign-up to receive these regular newsletters:

• TREC Pānui (general newsletter)
• TREC Hawke's Bay regional update
• This TREC Tairāwhiti regional update

Local road network

Gisborne District Council is responsible for local roading recovery projects. More information.

Up-to-date information on local road closures.